Magnetic tape as a data storage medium requires the ability effectively to write and read data to data tracks of the magnetic tape; many such data tracks typically extend linearly along the length of the tape and, in part, define tape data storage density. In recent years, much higher track densities have been achieved in tape through the inclusion of a dynamic track following servo system. In linear multi-channel tape systems, this has meant the addition of dedicated servo bands on the tape and dedicated servo read sensors on the recording/playback head to more accurately derive data element position relative to the data track. The servo tracks provide for the controlled movement of tape reading and/or writing heads with respect to the data tracks. Servo tracks typically are written in such a way as to span the tape in an efficient manner that maximizes the number of data tracks and minimizes the number of servo tracks for a given tape system, thereby increasing tape data storage capacity and density.
Servo tracks extend linearly along the length of the tape and contain servo data; the servo data is used to determine the relative position of the servo read head with respect to the magnetic media in a translating direction (i.e., movement across the width of the tape). The initial servo systems were amplitude based, in which individual adjacently contiguous servo tracks within the servo band were amplitude modulated to provide the head position information. More recently, much of the tape drive industry has moved to “time based” servo patterns. In such time based servo patterns, any errors in the servo data create positioning errors that distort the reading or writing of the data tracks. To prevent such distortions, it is important to minimize such errors in the servo data. The present invention addresses methods to minimize errors in the servo data and heads and magnetic media to practice such methods.